botanicus/scheduled-format

# frozen_string_literal: true

require 'parslet'

# @api private
class Parser < Parslet::Parser
  rule(:hour_strict) do
    (match['\d'].repeat(1) >> str(':') >> match['\d'].repeat(2, 2)).as(:hour)
  end

  rule(:start_time) do
    str('[') >> hour_strict.as(:start_time) >> str(']') >> str(' ').maybe
  end

  rule(:time_frame) do
    # TODO: (hour_strict.absent? >> match['^\]\n'] >> any)
    str('[') >> match['\w '].repeat.as(:str) >> str(']') >> str(' ').maybe
  end

  rule(:header) do
    # match['^\n'].repeat # This makes it hang!
    (str("\n").absent? >> any).repeat(1).as(:str) >> str("\n")
  end

  rule(:task_body) do
    (match['#\n'].absent? >> any).repeat.as(:str)
  end

  rule(:tag) do
    str('#') >> match['^\s'].repeat.as(:str) >> str(' ').maybe
  end

  rule(:task) do
    str('- ') >> (time_frame.as(:time_frame).maybe >> start_time.maybe >> task_body.as(:body) >> tag.as(:tag).repeat.as(:tags).maybe).as(:task) >> str("\n").repeat
  end

  rule(:task_group) do
    (header.as(:header) >> task.repeat.as(:tasks)).as(:task_group)
  end

  rule(:task_groups) do
    task_group.repeat(0)
  end

  root(:task_groups)
end

export { Parser }